Control pedal for motor vehicles

ABSTRACT

A resilient unit for biasing the control pedals (such as the friction clutch pedal and/or the brake pedal) of a motor vehicle in which the pedal biasing unit proper is a substantially complete convolution of steel wire, lying on a plane perpendicular to the axis of the pedal pivotal axis. The configuration of the resilient unit is such as to assist the driver both when depressing the pedal and when releasing the pedal, so that the physical effort required of the driver is in any case reduced.

United States Patent 1191 Pezza 1 Nov. 27, 1973 CONTROL PEDAL FOR MOTORVEHICLES [75] Inventor: Salvatore Pezra, Milan, Italy [73] Assignee:Alia Romeo S.p.A., Milan, Italy [22] Filed: Apr. 3, 1972 [21] App]. No.:240,750

[30] Foreign Application Priority Data Apr. 2, 1971 Italy 21380 13 71[52] US. Cl. 74/560 [51] G05g 1/14 [58] field of Search 74/560, 519,517,

[56] References Cited UNITED STATES PATENTS 3,236,120 2/1966 Fender74/512 X FOREIGN PATENTS OR APPLICATIONS 1,931,356 12/1970 Germany74/560 Primary Examiner--Charles J. Myhre Assistant Examiner--F. D.Shoemaker Attorney-John C. Holman et al.

[5 7 ABSTRACT A resilient unit for biasing the control pedals (such asthe friction clutch pedal and/or the brake pedal) of a motor vehicle inwhich the pedal biasing unit proper is a substantially completeconvolution of steel wire, lying on a plane perpendicular to the axis ofthe pedal pivotal axis. The configuration of the resilient unit is suchas to assist the driver both when depressing the pedal and whenreleasing the pedal, so that the physical effort required of the driveris in any case reduced.

3 Claims, 2 Drawing Figures CONTROL PEDAL FOR MOTOR VEHICLES BACKGROUNDOF THE INVENTION This invention relates to a control pedal for motorvehicles, which equipped with a yieldingly deformable member adapted todiminish the force to be imparted by the driver for depressing the pedaland for having the pedal to be brought back to the starting position.

In order to actuate the motor vehiclepedals, considerable forces arerequired, which, however, should not be exceedingly high for a person ofnormal build. Among the factors which causes tiredness for thedn'ver isto be obliged to impress such forces frequently, as occurs when drivingdowntown or during particular maneuvers, such as parking maneuvers,during which the driver virtually continually depresses and releases thepedals.

The approaches which provide for automatic mechanisms are too expensivefor certain types of motor vehi cles and, sometimes, are not appreciatedby the motorists since they suppress the pleasure of driving the car, asthe latter becomes virtually a self-driving unit.

PRIOR ART A solution to this problem is known, which permits to fulfilthese contrasting requirements and which consists in applying to thepedal resilient means which, by their agency, assist the muscular forceof the driveras he depresses the pedal or, as an alternative, when heallows the pedal to revert to the rest position, so that the maneuversare directed by the driver, but the effort which is required to effectthese operations is partly supplied by the driver and partly by theelastic energy which has been stored by the resilient means as appliedto the pedal.

The conventional mechamisms are equipped with springs which act bytorsional twist or by bending, and which are pivoted for rotation bothto the pedal arm and to a point fixed in space in the vehicle. As thepedal, by being rotated about its pivotal point, has gone past aposition, which is called load inversion position or dead centerposition", in which the pivot is aligned both with the point at whichthe spring is affixed to the arm and to the point at which the spring isfastened to the vehicle body, the forces as generated by the spring showa tendency to rotate the pedal about its pivotal point, in the directionof pedal depression until attaining the end of stroke position, or, asan altemative, until the pedal is brought back .to its rest positionagain.

These conventionally known mechanisms involve bulk problems which aredifficult to solve, due to space shortage in the vicinity of the pedals,especially in motor cars, so that one is often compelled to give uptheir adoption.

SUMMARY OF THE INVENTION The pedal, subject of the present invention,which has been designed with a view of eliminating the above indicatedshortcomings, while simultaneously affording stresses to which it issubjected. The above indicated resiliently deformable element is definedby a single substantially complete convolution of steel, having acircular cross-sectional shape and pivotally connected at one end to thevehicle body and, at the opposite end, to the pedal arm (preferablybetween the pivotal point and the pedal plate in order to obtain a morecompact structure, but also on an extension of the arm, wheneversufficient space is available under the hood).

The above indicated element is, of course, preloaded as a function ofthe work to be supplied thereby and is 1 arranged at an appropriatelocation relative to the an economically acceptable solution, isequipped with pedal according to the direction of the displacement to beeffected by the pedal. 7

A preferred embodiment of the invention is shown diagrammatically in theaccompanying drawing, given by way of nonlimiting example.

BRIEF DESCRIPTION OF THE INVENTION FIG. 1 shows a side elevational viewof the pedal and FIG. 2 is a front view of a portion of the pedal incross-section.

The numeral 1 indicates the pedal plate, on which the drivers footrests, with the plate being integral with an arm 2 which is pivoted forrotation to a pin 3 which is affixed, in the example shown, to a pedalbox 4.

Integral with the pedal arm 2 there are the members (not shown sincethey are not within the field of the present invention) which, through aleverage, or, as an alternative, through a hydraulic circuitry, control,for example, the friction clutch or the brakes of the vehicle. FIG. Ishows hole 14 which permits such a connection to be effected.

At 5 there is indicated the resilient member which consists of asubstantiallycomplete steel convolution, lying on a plane perpendicularto the axis 10 of the pin 3. At 11 there is indicated the end point ofthe spiral in correspondence with which the steel wire forming theresilient member is bent so as to form an arm 7, which is rotatablypivoted to a bushing 9. The bushing is solid with a supporting tag 15,with the tag being affixed to the pedal box 4 and numeral 12 indicatesthe end point of the spiral in correspondence with which the wireforming the resilient member is bent to form an arm 6, which is pivotedfor rotation to a bushing 8. The bushing 8 is integral with the pedalarm 2, inasmuch as the arm 6 of the resilient member is connected to thepedal arm 2 at a point midway between the pivot (axis 10) and the plate1.

The box 4 is fastened with conventional means to the sheet metal of adashboard 13 which, in the vicinity of the pedal, has a perforation l6permitting the pedal to emerge therefrom. In the case in point, as theresilient member 5 is positioned with respect to the pedal as shown inthe drawings, when the driver depresses the pedal, during a firstportion of the stroke, he must overcome the bias of the resilient meansapplied, for example, to the friction clutch or to the brakes, whichcounteract the pedal depressing force and, in addition, also the bias ofthe resilient member 5 which tends to lift the pedal in the restposition, until the pedal, under the driver push, attains the loadinversion position (dead' center), a position where the axis of the pin3 is aligned with both the axis of the arm 6 and with that of the arm 7,in the sense that both these axes lie on a single plane which isperpendicular to the plane of the drawing FIG. 1. Beyond the positionaforementioned, the resilient member 5 imparts to the pedal a forcedirected in the same direction as the force impressed by the driver, sothat, of the work necessary to depress the pedal fully, a portion issupplied by the driver and a portion by the resilient memberaforementioned, which, by being still moved on the plane perpendicularto the axis of the pedal pin 3, is brought to the position shown inchain dotted lines in FIG. 1, corresponding to the position in which thepedal is fully depressed (also shown in FIG. 1 in chain dotted lines).

During the pedal return stroke, up to the position of load reversal(dead center) the resilient member 5 acts contrarywise with respect tothe direction of movement and the pedal is pushed so as to return to therest position by the resilient means, as applied, in the manner recalledabove, either to the friction clutch or to the brakes, and which are nolonger hindered by the drivers action, and, conjointly, by thepedal-biasing resilient means.

In the last portion of the return stroke, once the load inversionposition has been overcome, the resilient member 5 acts upon the pedalin the same direction as the resilient means of the friction clutch orthe brakes and tends to bring the pedal back to the rest position.

Springs are often applied to the pedal arm in order to ensure that thepedal is brought back to the rest position and is held fully lifted.

The resilient member 5 can assist, or even replace, the springsaforementioned, since it is capable of impressing, in the last portionof the return stroke, a pull towards the rest position of the pedal, inthe sense of keeping it lifted. Also the torsion or bending springsapplied to the pedal in the conventional structures, fulfil thisrequirement, but the advantage stemming from the solution suggestedabove is apparent as regards the re duction of bulk, the more so that ina few cars space shortage does not allow the introduction of theconventional kinds of torsion or bending springs in order to assist thedrivers force.

What is claimed is:

1. A control pedal for motor vehicles including a pedal arm havingopposite ends. A pivot for one end of the pedal arm for attachment tothe vehicle frame, a pedal plate carried by the other end of the pedalarm, a support means located laterally with respect to the pedal arm,and a preloaded resilient deformable member operatively connected to thesupport means and the pedal arm serving to diminish the force to beimparted by a driver for depressing the pedal plate and for causing thepedal plate to return to its starting position, said resilientdeformable member comprising a single substantially complete convolutionof steel having a circular cross-sectional outline, said convolutionlying on a plane perpendicular to the axis of'the pivot for the pedalarm and having two end points, means rotatably pivoting one end point tothe support means, and means rotatably pivoting the other end point tothepedal arm.

2. The control pedal for motor vehicles as claimed in claim 1 in whicheach end point is defined by an arm extending normal to the plane of theconvolution, one arm extending toward the support means and the otherarm toward the pedal arm, and a bushing in each of said support meansand pedal arm in which said one arm and said other arm are receivedrespectively.

3. The control pedal for motor vehicles as claimed in claim 1 in whichsaid other end point is rotatably pivoted to the pedal arrn intermediatethe pedal plate and the pivot for the pedal arm.

1. A control pedal for motor vehicles including a pedal arm havingopposite ends. A pivot for one end of the pedal arm for attachment tothe vehicle frame, a pedal plate carried by the other end of the pedalarm, a support means located laterally with respect to the pedal arm,and a preloaded resilient deformable member operatively connected to thesupport means and the pedal arm serving to diminish the force to beimparted by a driver for depressing the pedal plate and for causing thepedal plate to return to its starting position, said resilientdeformable member comprising a single substantially complete convolutionof steel having a circular cross-sectional outline, said convolutionlying on a plane perpendicular to the axis of the pivot for the pedalarm and having two end points, means rotatably pivoting one end point tothe support means, and means rotatably pivoting the other end point tothe pedal arm.
 2. The control pedal for motor vehicles as claimed inclaim 1 in which each end point is defined by an arm extending normal tothe plane of the convolution, one arm extending toward the support meansand the other arm toward the pedal arm, and a bushing in each of saidsupport means and pedal arm in which said one arm and said other arm arereceived respectively.
 3. The control pedal for motor vehicles asclaimed in claim 1 in which said other end point is rotatably pivoted tothe pedal arm intermediate the pedal plate and the pivot for the pedalarm.